Recently, an increasing number of articles of clothing, such as shoes, boots, gloves, coats, jackets and pants, have been manufactured as waterproof clothing. This clothing often does not have a waterproof outer layer but is lined with a waterproof, water vapor-permeable function layer which is supposed to prevent moisture reaching the inside or inner lining of the clothing.
Although this type of clothing is supposed to be waterproof, there are often places which are not waterproof. This is usually caused by processing errors or manufacturing methods which cause water permeability while the clothing is being made. Frequently, water bridges are formed between the outside and the inside of the function layer or the inner lining of the clothing by means of seam holes or seam threads. Also, threads or pieces of cloth which are not properly trimmed and therefore project over the cut ends of the function layer frequently result in water bridges. This causes water to collect on the inside of the clothing then seep into the lining. For example, these water bridges cause the inner lining of waterproof shoes to become damp shortly after the outside of the shoe becomes wet.
So far, the so-called PFI tester of the Testing and Research Institute of the Shoe Industry has been used to test shoes for waterproofness. This testing device consists of a steel shoe tree which is formed like shoe tree in the toe area only, and otherwise is shaped like a narrow strap. This steel shoe tree is designed with a spring-loaded joint in the flex area of the shoe, i.e. where a fold forms during walking at the base of the toes. This enables the shoe tree-like tip to be raised against the spring force and returned to its resting position. For this purpose, the shoe to be tested, which is pulled over the shoe tree, is placed with its heel on a stationary steel plate and with its toe area on a movable steel plate. This steel plate is moved in a way which has both a horizontal and a vertical component. This requires an expensive mechanism which is submerged in the water bath, which is especially corrosive due to the tannic acid discharged from the shoes to be tested, attacks the mechanism and eventually damages it.
Moreover, the steel shoe tree known in the art, which is shaped like a narrow steel strap or steel rod up to the toe of the shoe, only comes in contact with the shoe in two places of realtively small area. Due to pressure from the base plate, this steel shoe tree moves in the shoe. At the support points between the steel shoe tree and shoe, a chafing or rubbing of the lining and thus of the waterproof function layer can occur. if moisture is detected in the shoe, it is difficult to determine whether it has penetrated due to a chafed function layer or due to water bridges caused by the system or during manufacture.
In the shoe tester known in the art, the test for waterproofness is carried out by looking at and feeling the shoe removed from the shoe tree. Frequently, filter paper is placed in the removed shoe in order to possibly determine the presence of penetrated water. The number of cycles at which the service person stops the shoe tester, removes the shoe from the water and examines the inside of the shoe for penetrated moisture is purely coincidental.
The shoe tester known in the art is only designed for testing a very specific shoe size. If a shorter shoe tree for a smaller shoe were placed on the clamp, the base plate which moves up and down would no longer be in the proper place under the toe area of the small shoe. Correspondingly, the opposite applies to a shoe which is larger than the one stipulated for the shoe tester.
Other waterproof articles of clothing, such as gloves, jackets, pants and coats, should also be tested for waterproofness. So far, it has not been possible to test these articles of clothing in their entirety. Only a section of material from an article of clothing to be tested has been loaded with a water column of defined height and tested for waterproofness. So far, it has not been possible to determine how entire articles of clothing behave when they are worn and where the particularly sensitive places are located.
One purpose this invention is to make available a device for testing articles of clothing for waterproofness which provides a high degree of measurement accuracy, reliability and expressiveness in a situation which simulates actual use as closely as possible.